The present invention relates generally to imaging devices, and more particularly to devices for detecting and identifying light emitting events.
Prior art imaging devices may comprise a rotating spectral separation element or subassembly installed in the collimated space of an imaging lens that is focused on a focal plane array and then may use spectro-tomographic image processing techniques to extract hyperspectral image data. Prior art imaging devices also may comprise a spectral separation element or subassembly placed in front of the imaging lens of a single channel imaging system comprised of an imaging lens focused on a focal plane array. The prior art imaging devices may receive light from a light-emitting event occurring within a scene. The emitted light travels through the spectral separation element or subassembly while the spectral separation element or subassembly is either in a fixed position or is rotating and is then received by the focal plane array. The focal plane array transmits information related to the received light to a processor. Thereafter, if the spectral separation element or subassembly is rotated to a second angular position, and the emitted light travels through the spectral separation element or subassembly and is received by the focal plane array, the focal plane array then transmits this information related to the received light to the processor and spectro-tomographic image proceesing is used to extract spatially organized spectral information. This process of spectral separation, reception and transmission is continued until the light-emitting event may be identified by the processor based on the transmitted information.
There are several shortcomings to the prior art. While the systems described are collecting this spectral information, they cannot collect broadband image information. Another problem is that in order to locate the source of a light-emitting event within the sensors' field of view in the case where the spectral separation element or subassembly rotates, the spectral separation element or subassembly must rotate enough to generate an arc in the light spectrum received by the focal plane array that is collected over several frames of the focal plane array in order to locate the position of the light-emitting event. This process takes-time-and requires that several frames of focal plane array imagery be processed. In order to perform this location function on short time events, the spectral separation element or subassembly must rotate at high rates, the focal plane array must operate at high frame rates that is transmitted to the processor at high rates that drives the required capability of the processor to a higher level. Another problem associated with the prior art imaging devices is that the prior art imaging devices must be stable for proper operation.
Accordingly, there is a need in the art for an improved imaging device.